Tires

All posts tagged Tires

When I brought the 2013 SFV650 in for its inspection this spring, the shop thought it was about time to invest in some new tires. The bike had Dunlop Sportmax Qualifiers installed which were the OEM tire and they had almost 9,000 miles on them which is pretty good life for a motorcycle tire. For the replacement tires I went with the Michelin Pilot Road 4 tires which have many good reviews and seem to be inline with my riding style.

I started with the front wheel and it is easiest if both front brake calipers are removed first. I hung them from the handlebar with some bungee cords.

I used the Motion Pro BeadPro tire bead breaker and tire lever set to both remove and install the tires. They work well at breaking the existing tire bead and have enough length to get the tires off and on the rim. Definitely use some rim protectors to avoid scuffing up the rim. I also used Windex on the old tire to help it slip off of the rim with the tire levers and then used Yamalube Tire Mount Lube to assist with seating the new tire bead.

The front tire with its narrower width is both easier to remove and install than the rear wheel.

Previously I mounted new tires on the 1981 Suzuki GS650L due to their age and for balancing I used Dynabeads as shown in this post. The Dynabeads seemed to work fine, but I wasn’t sure if some of the steering feel of the GS650L was influenced by the Dynabeads or if it was just the geometry of the older bike. For this bike that I ride on a more regular basis, I wanted to properly balance the tires. The Michelin tires do not come with a balancing mark on the tire, so you just mount it on the rim in any location. Michelin seems to think that any weight imbalance in the tire itself is insignificant and that most balancing is done for the weight of the wheel. The front wheel did not have any balance weights before I started. Using the Tusk Static Wheel Balance Stand I had to add 7g of weight to the rim to find the balance point.

The rear wheel was even a bit more difficult to remove from the bike. The rear axle has a 27mm nut. Even with this socket on a 1/2″ breaker bar, I had to add another length of pipe to the handle to get enough leverage to break the nut free. Once you pull the rear axle out, the rear brake caliper is also released from the swing arm and is just flipped forward out of the way in the next photo.

With the added width of the rear tire and rim, the bead would not seat with air pressure alone. Adding a ratchet strap around the circumference of the tire and cranking it down to the rim allowed the tire to inflate and set the bead.

You can see in the photo that the original tire had two 20g crimp on weights installed for balance. Since the belief was that the imbalance was in the wheel I left them on to check the initial balance. That was now the heavy spot on the new tire. I took the weights off and re-balanced with the stick-on 7g weights. It ended up using 42g of weight only slightly off from where the original 40g of weight was crimped on. Oh well.

Everything was reinstalled to the bike and torqued to specification. The new tires do have a nice feel while riding. I will be curios to see how long they hold up with the dual compound tread technology.

A before and after of the Dunlop Sportmax Qualifiers vs, the Michelin Pilot Road 4:

Advertisements

Share this:

Like this:

I mentioned when I replaced the rear tire that I probably should have used an angled valve stem to make tire filling and valve core removal easier, but I am not going to dismount the rear tire just for that purpose. Because of the tight clearance I couldn’t get my valve core tool to remove the core and allow filling the rear tire with the Dyna Beads for balancing. I recently found a 4-way valve core tool from Slime that did the trick and the Dyna Beads are now installed in the rear tire.

Motion Pro valve core tool won’t fit with the large rear hub of the shaft drive.

No problem with clearance for the Slime 4-way valve core tool.

Loading up the beads.

These beads could be fun for the next person that attempts to change the tire if they don’t know that they are inside. I recently heard a suggestion of drilling a hole in the outside of the old tire so that you could capture the existing beads before removing the tire from the rim…

Share this:

Like this:

Even though the rear tire was still holding air and had plenty of tread left, I wanted to replace it to match the new front tire and due to the fact that it’s manufacturing date was 2005. Wouldn’t want it to start tearing apart once a load was applied to it.

The rear tire turned out to be a bit more challenging to replace than the front. The front wheel removal only involved removing the axle bolt and jacking up the front end of the motorcycle to get the wheel two drop out of the front brake caliper. The front brake caliper could have been removed to make it a little easier, but it wasn’t necessary.

On the rear tire, the manual indicates that you need to remove the brake caliper and the rear shocks so that the rear wheel can drop down below the exhaust pipes to remove the axle and then slide the wheel to the right to disengage it from the shaft drive.

Now the new front tire is not that much taller than the original, 100/90 vs. 90/90, but there was no way the rear wheel was going to drop far enough to get the axle past the exhaust, so the front wheel had to come back off to lower the front end and allow the rear swing arm to drop more pivoting about the center stand. Here is what it looked like when the rear wheel was able to be removed.

The rear tire size is 130/90-16 and a bit more than my hands could handle. On the front tire I was able to break the bead with just my hands, but that wasn’t going to happen with the rear, so I created a 2×4 bead breaking station in the shed and even with that it still took one person standing on the tire to hold it down, Thanks Dad!, and one on the lever to apply pressure to the bead and break it on both sides.

The 2×4 lever had quite a bit of bend to break the bead. Mounting it in a vertical orientation with a pivot bolt connecting it to the stud would have probably been stronger, but I had the hinge lying around.

I was then able to get the old tire off with tire levers again.

To install the new tire I gave the lashing strap idea a try thinking that it might work better with the wider tire, but it still didn’t work for me. Back to the tire levers and Yamalube Tire Mounting Lube and the new tire was on the rim. Had some trouble trying to get the bead to seat and air up the tire, but some more Yamalube and air pressure took care of that.

I probably should have purchased a 45° valve stem for this wheel, but the original was straight so I didn’t even think about it. It is a tight squeeze to get the air chuck in there and my valve core tool doesn’t fit within the available space. I need to remove the core to add the Dyna Beads, but that can wait for a bit while I start to work on the brakes.

Share this:

Like this:

The front tire was not holding air very long when I purchased the bike and date codes on the tires indicate that the front tire was manufactured in 2003 and the rear in 2005. These are tubless tires and even if I could solve the air holding issue, the tires are probably past their useful age. Unlike an automobile, a motorcycle only has two tires and they are key to your successful ride.

Original tire sizes on this motorcycle are 90/90-19 on the front and 130/90-16 on the rear. It does not appear that many manufacturers make the 90/90-19 tire anymore and most GS riders have switched to 100/90-19 on the front to broaden the tire choices and it appears to also remove some inaccuracy in the speedometer with a slightly taller tire. I only found the Pirelli MT66 that would be able to have the original tire sizes in a matching pair of front and rear tires.

I went with the Shinko 230 Tour Master tires which have good reviews and were only $130 for the pair. Shinko is a Japanese company that bought the Yokohama motorcycle tire line and now produces the tires outside of Japan to keep costs down. I also bought new valve stems and cores for each wheel since that is probably where the air leak was occurring on the front tire.

The sad, original front tire:

I looked into different methods of removing and installing motorcycle tires with many people promoting methods that use zip ties or lashing straps to squeeze the tire inner diameter to make it fit over the rim easier, but I found good old tire levers to be the easiest method on the front tire. I also used Yamalube Tire Mount Lube with the tire levers for the installation of the new tire.

I then replaced the valve stem before mounting the new tire.

The old valve stem on the left only had an air sealing rubber grommet on the inside of the rim. The old valve steam was also showing a lot of corrosion and grit around the grommet. The new valve stem has a two part grommet with one on the outside and one on the inside. Hopefully this will provide a better seal.

Once the tire is mounted and inflated, the next step in the process is the balancing of the tire to prevent vibrations. The original wheel used clip on weights for balancing and this can be checked through a trial and error process by rotating the wheel on a stand to determine where the heavy spot is located, but you still won’t know the precise weight differential. Rather than try to find the necessary clip on weights and do the trial and error approach, I am going to try using a product called Dyna Beads. This product adds small ceramic beads to the inside of the tire that are supposed to gravitate to the lighter areas of the tire to provide balance and is a continual process as the tire wears.

For the tire sizes on this motorcycle, 1 ounce of beads is used in the front tire and 2 ounces in the rear tire.

This photo shows the traditional clip on weight at the top, the 1 ounce and 2 ounce bags of ceramic beads, and the applicator bottle.

All you need to do is remove the valve core and pour in the beads.

The new tire is reinstalled and technically the bike is now ready to ride, but there are still a few things that I would like to do such as the rear tire replacement and checking out the brakes.